1. Field of the Invention
The present invention relates to an imaging apparatus which comprises an indicator unit to notify a user of a degree of inclination of the apparatus relative to a horizontal plane or presence of inclination thereof, and automatically switching means to notify them in accordance with a held state and/or fixed state of the apparatus.
2. Description of Related Art
There is a known imaging apparatus (camera) which has a function as a spirit level to detect a posture of the apparatus and notify a user of amount of inclination thereof and/or a direction of the inclination relative to a horizontal direction (orthogonal to direction of gravity). For example, Japanese Laid-open Patent Application Publication No. 2006-287768 discloses an imaging apparatus which notifies inclination of the apparatus to a user by changing illumination patterns of an LED for focus adjustment.
Further, Japanese Laid-open Patent Application Publication No. 2004-343476 discloses an imaging apparatus which displays an indicator of stick-like pattern superimposedly on a subject image on a screen at shooting, to indicate a current inclination with a moving index mark as a spirit level does and help a user know the posture of the imaging apparatus (inclination of a captured image). However, there is a problem in this imaging apparatus that since the index mark continuously moves in the indicator in accordance with the inclination of the apparatus unless the apparatus becomes completely still, it is difficult for the user to know when it becomes horizontal. In addition, the indicator can be a visual annoyance to the user.
Further, Japanese Patent No. 3896505 discloses an imaging apparatus which assists a user to know the posture of the apparatus or the inclination of a captured image by displaying a referential horizontal line and an assist line indicating a current posture of the apparatus on a screen.
Moreover, Japanese Laid-open Patent Application Publication No. 2006-165941 discloses an imaging apparatus which assists a user to know the posture of the apparatus or the inclination of a captured image by displaying grid lines indicating a referential horizontal state and a horizontal line indicating a current horizontal direction of the apparatus in different colors and displaying the grid lines in a different color from the original colors of both of the lines when the horizontal line coincides with one of the grid lines.
However, these imaging apparatuses have a similar problem that the assist line (horizontal line) constantly moves in accordance with the inclination of the apparatus unless the apparatus becomes completely still. Therefore, it is difficult for the user to know when the apparatus becomes horizontal, and the assist line can be a visual annoyance to the user. In addition, since the assist line (horizontal line) getting across the display screen is inclined according to the inclination of the apparatus, affected by resolution of a screen or the like, it may be an unevenly stepwise line instead of a smooth straight line, which may degrade visual quality of the display and cause the user to feel annoyance.
Here, in terms of adjustability of an inclination relative to a horizontal direction, how accurately the imaging apparatus can be adjusted changes depending on a state of the apparatus, that is, held state and/or fixed state (hand-held, fixed by a tripod, for example).
However, the prior art imaging apparatuses above are configured to notify the amount and/or direction of inclination of the apparatus to the user with a constant resolution irrespective of which of states, the held or fixed state or held and fixed state the apparatus is in. The user adjusts the posture of the apparatus based on the notified amount or direction. Because of this, when the resolution of the notified amount or direction of inclination exceeds the resolution at which the user can adjust it manually, it may be difficult and take a lot of time for the user to adjust the posture of the apparatus to a desirable level.
In contrast, when the resolution of the notified amount or direction of inclination is far below the resolution at which the user can adjust it manually, captured images with the adjusted imaging apparatus may still have the amount or direction of inclination and are not satisfiable for the user.
Thus, the prior art imaging apparatuses have another problem that with a large difference in the amount and/or direction of inclination which the user can adjust manually and which the imaging apparatus notifies to the user, the user cannot adjust the amount/direction of inclination, or the posture thereof in a short time easily to capture a desirable image.